AS HE GROWS Taj Mahal is achieving more by putting out less. From its first song his new album relaxes, and leaves the walls of sound around which he wrote The Natch'l Blues for a looser and quieter feel. Taj cuts his voice so far down in volume that he sounds like Mississippi John Hurt, crooning, bending the pitch, working hoarsely against the instruments' rhythmic line. While he becomes more reserved in volume and tone, he is getting more expressive in range and rhythm.

"You're Gonna Need Somebody On Your Bond," the strongest song Taj has recorded, begins with two quiet vocal stanzas. It discards the conventional big-band blues structure which starts solidly and builds gradually to a big brassy climax and cuts rapidly out-like "Corinna," the finest song on The Natch'l Blues. Taj interrupts the words of "You're Gonna Need" after only two stanzas for purely melodic development on his harmonica. That's early to cut off your verse-development and go into formal elaboration. Taj on harmonica builds to a climax rhythmically and melodically-but not in volume-then cuts back to voice for a single loud stanza. Though the following five stanzas get even more emotional, moving all over his range and tone, they aren't loud. He works his vocal line intricately against the bass line. To share his excitement you have to explore the song with him instead of sitting back and letting a single surface of sound hit you.

Taj has discarded the solid wall of sound that modern blues bands use. But though his latest songs thereby become more open and varied, they aren't less unified. Taj's style is closer than ever to the subjects of his songs, more responsive to their nuances of wording and twists of mood. It's also closer to old country blues, one of the most unified kinds of music ever heard.

BUT TAJ can't go all the way back to his roots in country music and still move his own music forward. De Ole Folks at Home, the companion disk to Giant Step, proves as much. The very title gives you pause: it promises an instant replay of an immense tradition. But some of the work he does in that tradition is original and versatile. In "A Little Soulful Tune" he fashions a complete. song with hands and voice alone.

Unfortunately, about half the record's songs confirm the presumption of its title. Taj imitates Mississippi John Hurt. Leadbelly, Gray Davis, and others. He's good at it; he can play and sing like John Hurt if he pleases; and you can't help admiring the guts of a man who takes on the King of the Twelve-String. But Taj isn't as good as the masters yet. And even if he were it would be stupid to play their songs the way they did. To put their versions on his albums is to take them from his tradition and add them to his personal accomplishments. That's no honest way to sell his albums or his image.

Moreover, these imitations aren't as creative, as personal, as emotionally rewarding as his own fourmany compositions on Giant Step. His replay of John Hurt's "Stacker Lee" is not as moving or as true to the word-structure of the song as Hurt's. His streamlining of Leadbelly's "Take Your Hands Off Her" recalls the outrages the Stones committed on the Reverend Robert Wilkins's "Prodigal Son." He shouldn't have tried to update it; Leadbelly's version has the unity, the weight, the intractability of bedrock. Whereas Taj's version of "Good Mornning, Little School Girl" is more assured, more aware of the song's traditional bases, than the Grateful Dead's. He and his backup men are subtler, funnier, and stronger because they don't try so hard every instant. Taj has taken the song back to country blues, where it belongs.

The same relaxed seriousness runs throught his new song "Giant Step":

Remember the feeling as a child

When you woke up and morning smiled

It's time, it's time, it's time you felt like that again.

When I was younger and wiser I used to fall alseep listening to my brother play country songs on his Stella. I know "Stacker Lee" and "Prodigal Son" the way Hurt and Wilkins played them; they're part of my feelings about structure and right order. Taj doesn't have to copy them to evoke these feelings. His own new songs can bring an audience back into that true structure, that exploratory engagement with their material:

There is just no percentage in remembering the past

It's time to learn to live and love again and last

(Leave) yesterday, oh yesterday oh yesterday behind

And take a giant step outside your mind.